diff options
Diffstat (limited to 'package/kernel/gpio-nct5104d/src/gpio-nct5104d.c')
-rw-r--r-- | package/kernel/gpio-nct5104d/src/gpio-nct5104d.c | 461 |
1 files changed, 461 insertions, 0 deletions
diff --git a/package/kernel/gpio-nct5104d/src/gpio-nct5104d.c b/package/kernel/gpio-nct5104d/src/gpio-nct5104d.c new file mode 100644 index 0000000000..a37a1d056d --- /dev/null +++ b/package/kernel/gpio-nct5104d/src/gpio-nct5104d.c @@ -0,0 +1,461 @@ +/* + * GPIO driver for NCT5104D + * + * Author: Tasanakorn Phaipool <tasanakorn@gmail.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/gpio.h> +#include <linux/version.h> +#include <linux/dmi.h> +#include <linux/string.h> + +#define DRVNAME "gpio-nct5104d" + +/* + * Super-I/O registers + */ +#define SIO_LDSEL 0x07 /* Logical device select */ +#define SIO_CHIPID 0x20 /* Chaip ID (2 bytes) */ +#define SIO_GPIO_ENABLE 0x30 /* GPIO enable */ +#define SIO_GPIO1_MODE 0xE0 /* GPIO1 Mode OpenDrain/Push-Pull */ +#define SIO_GPIO2_MODE 0xE1 /* GPIO2 Mode OpenDrain/Push-Pull */ + +#define SIO_LD_GPIO 0x07 /* GPIO logical device */ +#define SIO_LD_GPIO_MODE 0x0F /* GPIO mode control device */ +#define SIO_UNLOCK_KEY 0x87 /* Key to enable Super-I/O */ +#define SIO_LOCK_KEY 0xAA /* Key to disable Super-I/O */ + +#define SIO_NCT5104D_ID 0x1061 /* Chip ID */ +#define SIO_PCENGINES_APU_NCT5104D_ID 0xc452 /* Chip ID */ + +enum chips { nct5104d }; + +static const char * const nct5104d_names[] = { + "nct5104d" +}; + +struct nct5104d_sio { + int addr; + enum chips type; +}; + +struct nct5104d_gpio_bank { + struct gpio_chip chip; + unsigned int regbase; + struct nct5104d_gpio_data *data; +}; + +struct nct5104d_gpio_data { + struct nct5104d_sio *sio; + int nr_bank; + struct nct5104d_gpio_bank *bank; +}; + +/* + * Super-I/O functions. + */ + +static inline int superio_inb(int base, int reg) +{ + outb(reg, base); + return inb(base + 1); +} + +static int superio_inw(int base, int reg) +{ + int val; + + outb(reg++, base); + val = inb(base + 1) << 8; + outb(reg, base); + val |= inb(base + 1); + + return val; +} + +static inline void superio_outb(int base, int reg, int val) +{ + outb(reg, base); + outb(val, base + 1); +} + +static inline int superio_enter(int base) +{ + /* Don't step on other drivers' I/O space by accident. */ + if (!request_muxed_region(base, 2, DRVNAME)) { + pr_err(DRVNAME "I/O address 0x%04x already in use\n", base); + return -EBUSY; + } + + /* According to the datasheet the key must be send twice. */ + outb(SIO_UNLOCK_KEY, base); + outb(SIO_UNLOCK_KEY, base); + + return 0; +} + +static inline void superio_select(int base, int ld) +{ + outb(SIO_LDSEL, base); + outb(ld, base + 1); +} + +static inline void superio_exit(int base) +{ + outb(SIO_LOCK_KEY, base); + release_region(base, 2); +} + +/* + * GPIO chip. + */ + +static int nct5104d_gpio_direction_in(struct gpio_chip *chip, unsigned offset); +static int nct5104d_gpio_get(struct gpio_chip *chip, unsigned offset); +static int nct5104d_gpio_direction_out(struct gpio_chip *chip, + unsigned offset, int value); +static void nct5104d_gpio_set(struct gpio_chip *chip, unsigned offset, int value); + +#define NCT5104D_GPIO_BANK(_base, _ngpio, _regbase) \ + { \ + .chip = { \ + .label = DRVNAME, \ + .owner = THIS_MODULE, \ + .direction_input = nct5104d_gpio_direction_in, \ + .get = nct5104d_gpio_get, \ + .direction_output = nct5104d_gpio_direction_out, \ + .set = nct5104d_gpio_set, \ + .base = _base, \ + .ngpio = _ngpio, \ + .can_sleep = true, \ + }, \ + .regbase = _regbase, \ + } + +#define gpio_dir(base) (base + 0) +#define gpio_data(base) (base + 1) + +static struct nct5104d_gpio_bank nct5104d_gpio_bank[] = { + NCT5104D_GPIO_BANK(0 , 8, 0xE0), + NCT5104D_GPIO_BANK(10, 8, 0xE4) +}; + +static int nct5104d_gpio_direction_in(struct gpio_chip *chip, unsigned offset) +{ + int err; + struct nct5104d_gpio_bank *bank = + container_of(chip, struct nct5104d_gpio_bank, chip); + struct nct5104d_sio *sio = bank->data->sio; + u8 dir; + + err = superio_enter(sio->addr); + if (err) + return err; + superio_select(sio->addr, SIO_LD_GPIO); + + dir = superio_inb(sio->addr, gpio_dir(bank->regbase)); + dir |= (1 << offset); + superio_outb(sio->addr, gpio_dir(bank->regbase), dir); + + superio_exit(sio->addr); + + return 0; +} + +static int nct5104d_gpio_get(struct gpio_chip *chip, unsigned offset) +{ + int err; + struct nct5104d_gpio_bank *bank = + container_of(chip, struct nct5104d_gpio_bank, chip); + struct nct5104d_sio *sio = bank->data->sio; + u8 data; + + err = superio_enter(sio->addr); + if (err) + return err; + superio_select(sio->addr, SIO_LD_GPIO); + + data = superio_inb(sio->addr, gpio_data(bank->regbase)); + + superio_exit(sio->addr); + + return !!(data & 1 << offset); +} + +static int nct5104d_gpio_direction_out(struct gpio_chip *chip, + unsigned offset, int value) +{ + int err; + struct nct5104d_gpio_bank *bank = + container_of(chip, struct nct5104d_gpio_bank, chip); + struct nct5104d_sio *sio = bank->data->sio; + u8 dir, data_out; + + err = superio_enter(sio->addr); + if (err) + return err; + superio_select(sio->addr, SIO_LD_GPIO); + + data_out = superio_inb(sio->addr, gpio_data(bank->regbase)); + if (value) + data_out |= (1 << offset); + else + data_out &= ~(1 << offset); + superio_outb(sio->addr, gpio_data(bank->regbase), data_out); + + dir = superio_inb(sio->addr, gpio_dir(bank->regbase)); + dir &= ~(1 << offset); + superio_outb(sio->addr, gpio_dir(bank->regbase), dir); + + superio_exit(sio->addr); + + return 0; +} + +static void nct5104d_gpio_set(struct gpio_chip *chip, unsigned offset, int value) +{ + int err; + struct nct5104d_gpio_bank *bank = + container_of(chip, struct nct5104d_gpio_bank, chip); + struct nct5104d_sio *sio = bank->data->sio; + u8 data_out; + + err = superio_enter(sio->addr); + if (err) + return; + superio_select(sio->addr, SIO_LD_GPIO); + + data_out = superio_inb(sio->addr, gpio_data(bank->regbase)); + if (value) + data_out |= (1 << offset); + else + data_out &= ~(1 << offset); + superio_outb(sio->addr, gpio_data(bank->regbase), data_out); + + superio_exit(sio->addr); +} + +/* + * Platform device and driver. + */ + +static int nct5104d_gpio_probe(struct platform_device *pdev) +{ + int err; + int i; + struct nct5104d_sio *sio = pdev->dev.platform_data; + struct nct5104d_gpio_data *data; + + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + switch (sio->type) { + case nct5104d: + data->nr_bank = ARRAY_SIZE(nct5104d_gpio_bank); + data->bank = nct5104d_gpio_bank; + break; + default: + return -ENODEV; + } + data->sio = sio; + + platform_set_drvdata(pdev, data); + + /* For each GPIO bank, register a GPIO chip. */ + for (i = 0; i < data->nr_bank; i++) { + struct nct5104d_gpio_bank *bank = &data->bank[i]; + + bank->chip.dev = &pdev->dev; + bank->data = data; + + err = gpiochip_add(&bank->chip); + if (err) { + dev_err(&pdev->dev, + "Failed to register gpiochip %d: %d\n", + i, err); + goto err_gpiochip; + } + } + + return 0; + +err_gpiochip: + for (i = i - 1; i >= 0; i--) { + struct nct5104d_gpio_bank *bank = &data->bank[i]; + +#if LINUX_VERSION_CODE < KERNEL_VERSION(3,18,0) + int rm_err = gpiochip_remove(&bank->chip); + if (rm_err < 0) + dev_err(&pdev->dev, + "Failed to remove gpiochip %d: %d\n", + i, rm_err); +#else /* LINUX_VERSION_CODE < KERNEL_VERSION(3,18,0) */ + gpiochip_remove (&bank->chip); +#endif /* LINUX_VERSION_CODE < KERNEL_VERSION(3,18,0) */ + } + + return err; +} + +static int nct5104d_gpio_remove(struct platform_device *pdev) +{ + int i; + struct nct5104d_gpio_data *data = platform_get_drvdata(pdev); + + for (i = 0; i < data->nr_bank; i++) { + struct nct5104d_gpio_bank *bank = &data->bank[i]; + +#if LINUX_VERSION_CODE < KERNEL_VERSION(3,18,0) + int err = gpiochip_remove(&bank->chip); + if (err) { + dev_err(&pdev->dev, + "Failed to remove GPIO gpiochip %d: %d\n", + i, err); + return err; + } +#else /* LINUX_VERSION_CODE < KERNEL_VERSION(3,18,0) */ + gpiochip_remove (&bank->chip); +#endif /* LINUX_VERSION_CODE < KERNEL_VERSION(3,18,0) */ + } + + return 0; +} + +static int __init nct5104d_find(int addr, struct nct5104d_sio *sio) +{ + int err; + u16 devid; + u8 gpio_cfg; + + err = superio_enter(addr); + if (err) + return err; + + err = -ENODEV; + + devid = superio_inw(addr, SIO_CHIPID); + switch (devid) { + case SIO_NCT5104D_ID: + case SIO_PCENGINES_APU_NCT5104D_ID: + sio->type = nct5104d; + /* enable GPIO0 and GPIO1 */ + superio_select(addr, SIO_LD_GPIO); + gpio_cfg = superio_inb(addr, SIO_GPIO_ENABLE); + gpio_cfg |= 0x03; + superio_outb(addr, SIO_GPIO_ENABLE, gpio_cfg); + break; + default: + pr_info(DRVNAME ": Unsupported device 0x%04x\n", devid); + goto err; + } + sio->addr = addr; + err = 0; + + pr_info(DRVNAME ": Found %s at %#x chip id 0x%04x\n", + nct5104d_names[sio->type], + (unsigned int) addr, + (int) superio_inw(addr, SIO_CHIPID)); + + superio_select(sio->addr, SIO_LD_GPIO_MODE); + superio_outb(sio->addr, SIO_GPIO1_MODE, 0x0); + superio_outb(sio->addr, SIO_GPIO2_MODE, 0x0); + +err: + superio_exit(addr); + return err; +} + +static struct platform_device *nct5104d_gpio_pdev; + +static int __init +nct5104d_gpio_device_add(const struct nct5104d_sio *sio) +{ + int err; + + nct5104d_gpio_pdev = platform_device_alloc(DRVNAME, -1); + if (!nct5104d_gpio_pdev) + pr_err(DRVNAME ": Error platform_device_alloc\n"); + if (!nct5104d_gpio_pdev) + return -ENOMEM; + + err = platform_device_add_data(nct5104d_gpio_pdev, + sio, sizeof(*sio)); + if (err) { + pr_err(DRVNAME "Platform data allocation failed\n"); + goto err; + } + + err = platform_device_add(nct5104d_gpio_pdev); + if (err) { + pr_err(DRVNAME "Device addition failed\n"); + goto err; + } + pr_info(DRVNAME ": Device added\n"); + return 0; + +err: + platform_device_put(nct5104d_gpio_pdev); + + return err; +} + +/* + */ + +static struct platform_driver nct5104d_gpio_driver = { + .driver = { + .owner = THIS_MODULE, + .name = DRVNAME, + }, + .probe = nct5104d_gpio_probe, + .remove = nct5104d_gpio_remove, +}; + +static int __init nct5104d_gpio_init(void) +{ + int err; + struct nct5104d_sio sio; + const char *board_vendor = dmi_get_system_info(DMI_BOARD_VENDOR); + const char *board_name = dmi_get_system_info(DMI_BOARD_NAME); + + /* Make sure we only run on PC Engine APU boards */ + if (!board_name || !board_vendor || strcasecmp(board_vendor, "PC Engines") || strncasecmp(board_name, "apu", 3)) { + return -ENODEV; + } + + if (nct5104d_find(0x2e, &sio) && + nct5104d_find(0x4e, &sio)) + return -ENODEV; + + err = platform_driver_register(&nct5104d_gpio_driver); + if (!err) { + pr_info(DRVNAME ": platform_driver_register\n"); + err = nct5104d_gpio_device_add(&sio); + if (err) + platform_driver_unregister(&nct5104d_gpio_driver); + } + + return err; +} +subsys_initcall(nct5104d_gpio_init); + +static void __exit nct5104d_gpio_exit(void) +{ + platform_device_unregister(nct5104d_gpio_pdev); + platform_driver_unregister(&nct5104d_gpio_driver); +} +module_exit(nct5104d_gpio_exit); + +MODULE_DESCRIPTION("GPIO driver for Super-I/O chips NCT5104D"); +MODULE_AUTHOR("Tasanakorn Phaipool <tasanakorn@gmail.com>"); +MODULE_LICENSE("GPL"); |